This invention relates generally to crop harvesting and threshing machines, more commonly known as combines, and more particularly, to the apparatus used to control the unloading auger by which cleaned grain is unloaded from the grain tank to a receiving vehicle. Specifically, the invention is directed to a mechanical control mechanism which allows the combine operator to activate the unloading auger by momentarily engaging the unloading auger control, permitting the auger to rotate off of the auger switch and then releasing the control, thereby having the unloading auger swing from the fully inboard or storage position to a predetermined outboard position automatically for the unloading of grain. This invention is applicable to all types of combines which utilize some type of grain unloading tube that must move between predetermined positions of non-operation and operation.
Traditionally combines utilize a grain storage system that has the threshed and cleaned grain transported by means of a collection trough and auger to an elevator which carries the cleaned grain upward into a receiving receptacle or grain tank. The grain is continuously fed into the grain tank during the operation of the combine as it harvests and threshes crop material in the field. The continuous field operation of a combine is generally limited by the capacity of the grain tank to store the clean grain. When the grain tank is full, the combine operator must normally cease the harvesting and threshing operation to unload grain from the grain tank to a receiving vehicle. Occasionally, this unloading operation is conducted simultaneously with the continued harvesting and threshing by having a receiving vehicle move alongside the combine as it progresses down the field. The receiving vehicle may either be a wagon towed behind a tractor or a large grain truck. These receiving vehicles haul the unloaded grain to appropriate storage areas generally remote from the field. This procedure is repeated continuously during the harvesting and threshing of the crop material.
Combine operators normally activate the unloading system by engaging a lever or a switch which requires that the operator continue its engagement during the entire time that it takes the unloading tube to swing from its inboard to its outboard position. Should the unloading operation be conducted while the combine continues to harvest and thresh crop material this requires the operator to direct his attention to several functions at one time. The operator must continually monitor the crop material which is being harvested to the front of the combine as it moves across the field, scan the numerous monitors displayed on the combine control panel and observe the movement of the unloading tube from the inboard to the fully outboard position which is utilized for unloading. Since the operator must continue to steer the combine during this time, this means that the operator must remove one of his hands from the steering wheels and simultaneously conduct at least two operations. Obviously this is a difficult and distracting procedure which could inadvertently cause the operator to vary from his desired path across a field. At the least, the continuous engagement of the unloading tube control mechanism is an inconvenience.
Recently, a control system utilizing electromechanical apparatus was designed for a combine which required the operator to momentarily engage a control mechanism which then automatically controls the movement of the unloading auger between the inboard and fully outboard positions. However, this type of a system is relatively complex and costly.
The foregoing problems are solved in the design of the machine comprising the present invention by permitting the combine operator to engage the unloading tube control momentarily, thereby activating a mechanical system which will permit the unloading tube to automatically swing from the full inboard to the fully outboard position without any further operator involvement.